Chromosome band-specific painting combines the techniques of microdissection of chromosome, in situ suppression hybridization (CISS) and polymerase chain reaction (PCR). This new method is useful for cytogenetic analysis and molecular cloning of chromosome specific DNA. However, the difficulties remain in the construction of a desired DNA probe pool, either by using chromosome sorter, or by collecting a large number of desired recombinant DNA clones from a microdissected DNA library. Both methods proved to be tedious and time consuming process. The most effective method is to remove a section from a specific chromosome band, and construct a probe pool directly from this band. This probe pool can be directly used to paint corresponding chromosome band. During our Phase I research, we have utilized the microdissection, microcloning and chromosome band-specific painting techniques, and constructed II chromosome band-specific DNA probe pools. For Phase II, we plan to continue improve and modify these techniques to construct additional probe pools. Our ultimate goal is to produce approximate 300 probe pools, thus, covering all bands at metaphase level. In addition, we will use these techniques to identify chromosome translocations, duplications and deletions at band levels, to help to develop standard diagnostic procedures for diseases caused by chromosome abnormalities, that are unidentifiable by the common cytogenetic techniques. Furthermore, we will apply the techniques to detect the origin of the marker chromosomes that are unidentifiable with routine cytogenetic techniques. Finally, we will characterize the DNA libraries produced by us, to generate polymorphic chromosome band-specific DNA probes or markers to facilitate mapping and cloning of the genes that are responsible for various types of genetic diseases.